Abstract

When wind flow passes around a structure, it generates in general, moment, lift and drag loads on the structure. If the shape of the structure is unstreamlined, which is the case with most bridge decks, then flow separation occurs, and organized vortices are shed. Sometimes the organized vortices are accompanied by smaller scale vortices. These vortices generate random pressure fluctuations in the wake, causing the structure, to move. In turn, the structure’s motion generates motion-dependent loads, referred to as self-excited loads. On the other hand, turbulence that generally exists in the oncoming wind generates additional external excitations which are independent of the structural motion and are referred to as the buffeting loads.